Conventional electrical outlets for outdoor use include a receptacle housed in a weatherproof outlet box which is closed by a weatherproof cover plate. For duplex outlets, the cover plate commonly has two openings and two flaps are mounted adjacent the openings. The flaps are hingedly mounted on the cover for movement between open and closed positions relative to the openings, and are spring biased towards their closed positions. The openings in the cover plate permit access to the contacts in the receptacle, while the flaps individually control that access.
Conventionally, a rubber gasket which overlies the electrical receptacle has been mounted between the cover plate and outlet box. This gasket has a single rectangular opening larger than or has two separate openings with transverse dimensions substantially equal to the transverse dimensions of the standard projections surrounding the contacts on the outlets such that this gasket merely provides seals between the outlet box and the cover plate. It does not provide seals with the cover plate flaps nor does it seal between the receptacle and cut-out openings in the cover plate. Thus, conventional outlets of this type require the use of separate gaskets or seals for the cover flaps and do not seal against an electrical plug connected to the receptacle.
The use of separate seals for the cover flaps results in increased manufacturing and assembly costs. Additionally, these separate seals increase the likelihood of leakage of contamination into the outlet box and into the receptacle, causing damage to and shorting of the electrical components. Moreover, the seal between the cover plate and the receptacle is susceptible to leakage in the conventional seal arrangement.
U.S. Pat. No. 4,058,358 to Carlisle discloses a one-piece, molded gasket, formed of rubber, for a covered electrical outlet box. The patent asserts that the gasket provides seals between the outlet box and cover plate, between the cover plate and receptacle, between the cover plate and the cover flap when the flap is closed and between the receptacle and a mating plug when the flap is opened (column 1, lines 6-12). However, the configuration of this gasket is complex, making the gasket difficult and expensive to manufacture, particularly by molding. Additionally, such molded gasket does not provide adequate seals between the cover plate and receptacle and with the mating plug. For a duplex outlet, the cover plate disclosed in the Carlisle patent has a single, large opening receiving the gasket projection and both receptacle projections, such that there is no central cover plate portion by which a single, centrally located screw can secure the cover plate to the receptacle, and thereby to the outlet box.